Field of the Invention
The present invention relates to a method of mounting an optical member, preferably used as a device of an optical communication apparatus or a computer, and an optical module using the optical member.
A microlens or a micro-optical device using a diffractive optical device is used as an optical member for optical communication or an optical disk reproduction device such as a CD player. Such a microlens has, e.g., a cylindrical shape or a hog-backed shape. The optical member of this type is manufactured such that a desired shape of a lens or the like is formed on, e.g., a silicon substrate by a photolithographic process and subjected to an etching process. The microlens or the micro-optical device has a size of about 100 μm square to several hundred micrometer square.
In general, the optical member is used on a support substrate such as a silicon substrate or the like. In the support substrate, a V-shaped groove having a V-shaped section and formed by etching or cutting, a terrace for arranging a semiconductor laser, a groove, being larger than a V-shaped groove, for arranging an optical member, or the like is formed. The V-shaped groove, terrace, groove, and the like are formed at high accuracy, the outlines of optical members to be arranged are formed at high accuracy in advance, and these optical members are arranged in the V-shaped groove or the like at a submicron accuracy, so that the optical members can be mounted at high accuracy. The optical members are arranged by using a component arrangement apparatus which is called a bonder.
When an optical module is manufactured by using the optical member constituted by a silicon substrate, in general, a mounting method which arranges the optical member in a V-shaped groove formed in a silicon support substrate and fixes the optical member is employed. As a fixing method, a method using an adhesive agent, solder, or the like is generally used.
However, in the mounting method, positioning is performed such that the optical member is brought into contact with the V-shaped groove, and the optical member which is in partial contact with the V-shaped groove is adhered and fixed to the V-shaped groove. For this reason, the fixing position of the optical member changes depending on the thickness of the adhesive agent, the positioning is not performed at high accuracy, and the mounting accuracy deteriorates. In addition, in the conventional mounting method, the optical member requires high accuracy with a large number of parts. When this condition is not satisfied, the optical member is determined as a defective optical member. This condition is an obstacle to an increase in yield.